usb: dwc3: Avoid waking up gadget during startxfer

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When operating in High-Speed, it is observed that DSTS[USBLNKST] doesn't
update link state immediately after receiving the wakeup interrupt. Since
wakeup event handler calls the resume callbacks, there is a chance that
function drivers can perform an ep queue, which in turn tries to perform
remote wakeup from send_gadget_ep_cmd(STARTXFER). This happens because
DSTS[[21:18] wasn't updated to U0 yet, it's observed that the latency of
DSTS can be in order of milli-seconds. Hence avoid calling gadget_wakeup
during startxfer to prevent unnecessarily issuing remote wakeup to host.

Fixes: c36d8e947a ("usb: dwc3: gadget: put link to U0 before Start Transfer")
Cc: stable@vger.kernel.org
Suggested-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20240828064302.3796315-1-quic_prashk@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Prashanth K 2024-08-28 12:13:02 +05:30 • committed by Greg Kroah-Hartman

parent 431c1646e1

commit 00dcf2fa44

1 changed files with 17 additions and 24 deletions

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drivers/usb/dwc3/gadget.c

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